Mark IV wont run on SV ammo - Page 1

[ARCHIVED THREAD] - Mark IV wont run on SV ammo

Posted: 12/2/2019 6:30:48 PM EDT

IIRC, when I first got my Mark IV, it ran fine on CCI SV ammo. Now it wont. I did put in a Volquartsen trigger in it, maybe thats when it quit working with SV. Anyone else run into this?

Posted: 12/2/2019 6:52:24 PM EDT

[#1]

Mine runs good with SV after putting better mag springs in the magazines. Tandomross "green" mag springs. Helps especially in winter/colder temps

When you say it doesnt run, what exactly is it doing?

Posted: 12/2/2019 7:18:57 PM EDT

[#2]

Wont lock back on last round, wont eject sometimes... Just not enough recoil to fully cycle the bolt.

Posted: 12/2/2019 7:35:33 PM EDT

[#3]

Mine had a few similar issues when the weather turned cold. Sometimes I switch out to CCI Mini Mags for the extra umph to cycle the gun. I run mine suppressed so it gets a bit dirty and needs a thorough cleaning every now and then.

I thought most the issues were with the gun, but it turned out to be the magazines not allowing the bullets to push upward fast enough to help the gun cycle. Mag spring changes as stated above solved that problem and mine run very well on CCI SV now. If there is any dragging on the mag follower it just wont run right.

Hopefully some others will chime in for suggested things to check.

Posted: 12/2/2019 7:48:29 PM EDT

[#4]

mine becomes a jamOmatic after just 50 rounds if I put my octane 45 hd on it

Posted: 12/2/2019 7:48:53 PM EDT

[#5]

I need to try them again to see exactly what its doing, but I just remember it needed more recoil. I just switched to higher velocity stuff and it worked, so I didnt give it much more thought. I think it would sometimes recoil enough to reset the trigger but still had the empty casing in the chamber. One strange thing is that it seems the bolt is easier to pull back manually than when it was new. Maybe Im just getting used to it.

Posted: 12/2/2019 8:11:48 PM EDT

[#6]

I run Volquartsen reduced power mainspring and recoil spring on mine to help with cycling as mine is a dedicated suppressor host. Cycles on anything except the quiets but I haven't given up on that yet.

Posted: 12/2/2019 8:35:23 PM EDT

[#7]

Install a VQ extractor. Do it.

Posted: 12/2/2019 8:50:35 PM EDT

[#8]

put the VQ trigger pack in mine, running an old Warlok. CCI stand velocity runs all day long in mine.

Putting in that pack will test you.

edit to add: I'm running a VQ bolt too.

Posted: 12/2/2019 9:02:37 PM EDT

[#9]

Quote History

Quoted:
Install a VQ extractor. Do it.

View Quote

I did when I did the trigger.

Posted: 12/2/2019 9:05:36 PM EDT

[#10]

Quote History

Quoted:
put the VQ trigger pack in mine, running an old Warlok. CCI stand velocity runs all day long in mine.

Putting in that pack will test you.

edit to add: I'm running a VQ bolt too.

View Quote

I keep reading on the net how easy it is... 15 min job. Maybe if I had done it 5-6 times before but I thought it was pretty tricky. Might have been drinkin' though.

Posted: 12/2/2019 9:14:33 PM EDT

[#11]

thats about all i feed my mkiv target and I installed the VQ accuracy kit. I did have to use the VQ sure fire firingpin.

Posted: 12/3/2019 5:25:39 AM EDT

[#12]

I followed the Tandem Kross video for modifying the mags for function and that helped a lot. I also just use cherry balmz rimfire remedy in my mark III and that has cured the majority of function issues. I do feed mine a steady diet of mini mags for competitive purposes but if I'm just going to the range I can slum it with standard velocity stuff.

Posted: 12/13/2019 6:35:22 PM EDT

[#13]

I shoot CCI STD Velocity all the time in Ruger MKIV 22/45 with Volquartsen parts and TandemKross trigger.
Although I am tempted to get the Volquartsen extractor.

Posted: 12/15/2019 1:23:43 AM EDT

[#14]

I had the same problem, and also noticed it increased when cold. I have discovered the solution. CCI SV has a wax like coating on the bullet that rubs off on the inside of the mag. This slows down the mag from feeding rounds fast enough. If you clean the mag function is restored. No real so,union to keep it from happening though. Switched to bulk pack which stays subsonic out of a pistol.

Posted: 12/15/2019 11:09:47 PM EDT

[#15]

PLus In colder weather the general rule is it takes more force for function, and as standard velocity ( especially if your gun is not well broken in) is sort of marginal to begin with the cold weather throws it over the edge

Posted: 3/22/2020 2:01:46 PM EDT

[#16]

Someone in GD suggested This spring kit from Volquartsen. I think I’m going to order one.

Posted: 4/8/2020 4:20:38 PM EDT

[#17]

Tried it out with the Volquartsen spring kit and it ran 150-200 rounds without a problem.

Posted: 4/8/2020 4:32:11 PM EDT

[#18]

I may be the only person on the internet that's almost completely happy with my bone stock Lite.

I was happy with the front site on the range. But under heavy tree cover I had a hard time seeing it, so I put in a fiber optic one.

I don't really wanna change anything. I'm a horrible consumer

Posted: 4/8/2020 8:56:15 PM EDT

[#19]

Quote History

Quoted:
Tried it out with the Volquartsen spring kit and it ran 150-200 rounds without a problem.

View Quote

I have that same kit on my MK III 22/45 Lite, and it works great with anything I feed it. I also have the reduced power mainspring...was trying to get it to cycle on 22 Quiet but no dice...Scott warned me it probably wouldn't work. I will say it's dead reliable now with SV and 22 Quiet SA ammo. Nice in Quiet with a can on it!

Posted: 4/9/2020 8:04:44 AM EDT

[#20]

Quote History

Quoted:

I have that same kit on my MK III 22/45 Lite, and it works great with anything I feed it. I also have the reduced power mainspring...was trying to get it to cycle on 22 Quiet but no dice...Scott warned me it probably wouldn't work. I will say it's dead reliable now with SV and 22 Quiet SA ammo. Nice in Quiet with a can on it!

View Quote View All Quotes

View All Quotes

Quote History

Quoted:

Quoted:
Tried it out with the Volquartsen spring kit and it ran 150-200 rounds without a problem.

I have that same kit on my MK III 22/45 Lite, and it works great with anything I feed it. I also have the reduced power mainspring...was trying to get it to cycle on 22 Quiet but no dice...Scott warned me it probably wouldn't work. I will say it's dead reliable now with SV and 22 Quiet SA ammo. Nice in Quiet with a can on it!

@-Obsessed-

I put the light spring on the Volquartsen guide and plan on switching back and forth between that and the factory spring assembly depending on what ammo I’m using. Is that what you are doing or do you just stick with low velocity ammo? What is the benefit of the reduced power mainspring?

Posted: 4/9/2020 8:17:51 AM EDT

[#21]

Quote History

Quoted:

@-Obsessed-

I put the light spring on the Volquartsen guide and plan on switching back and forth between that and the factory spring assembly depending on what ammo I’m using. Is that what you are doing or do you just stick with low velocity ammo? What is the benefit of the reduced power mainspring?

View Quote

I only run CCI, and I keep it to Quiet SA, SV, or Suppressor. I don’t have a desire to run higher velocity ammo. It won’t break the sound barrier most likely but it still has more powder and is louder. With that said I always keep the reduced power recoil spring installed.

The reduced power mainspring further reduces the energy needed to cycle fully. If you have the mainspring uncocked such as after a dry fire, run the bolt and you will feel the extra tension of the mainspring, and if you run the bolt again it’s much less effort as you’re only fighting the recoil spring at that point. Every time the gun fires it’s working against both springs so I wanted to try to reduce the power needed as much as possible. CCI Suppressor isn’t particularly powerful only being a hair more powerful than CCI Quiets so I wanted to further aid reliability shooting that particular ammo.

It’s a royal PITA to change though, so if you aren’t having issues I’m not sure I’d proactively do it.

Posted: 4/9/2020 9:07:15 AM EDT

[#22]

One thing I noticed when I first got my MarkIV was how hard it is to cycle the bolt after dry firing. I was thinking about getting one of those halo handles for the back of the bolt, but didn’t like the idea of the added weight. The reduced mainspring should help with that and is probably the way to go if you’re sticking with lower power ammo, as long as it doesn’t cause light strikes. It should reduce the trigger pull a little as a bonus. I just bought 10 boxes of these though.

Attached File

I think I will shoot a few of them with the light return spring, then the factory to see how much difference there is in felt recoil.

[ARCHIVED THREAD] - Mark IV wont run on SV ammo

Handguns » Rimfire Pistols

Warning

Confirm Action

About AR15.COM

Stay Connected

Newsletter

Contact Us